Foothill Yellow-legged Frog - Environmental Issues

Environmental Issues

Along with the problems associated with pesticides being washed up in the Foothill Yellow-Legged Frog's habitat, in Trinity County, California there is a dam on the major river of the frog's home which has affected about 94% of the possible procreation areas for the frogs, which has endangered the population. One study suggests that the “data from a comparably-sized undammed river fork in the same system…demonstrated that both the number of potential sites and the total number of egg masses were…higher on this fork than in our main stem,” and so the unseasonal flooding required by the dam was negatively affecting the mating behavior of the frog. The temperature of the water in Trinity County is also lower than it was before the dam was put into place. To keep up with demands of fisheries, the water’s temperature is kept artificially lower than normal, which consequently slows the development of R. boylii. Therefore, the colder temperatures are making it more difficult for the frogs to grow quickly, which sometimes leaves the species prey to many other animals that dine on their young. The problems occurring between the Foothill Yellow-Legged Frog and the dam are being handled by several herpetological organizations, along with the Forest Service, to find ways to alter the effects in a beneficial way for the frog. This species is also estimated to be gone from most of its range in the Sierra Nevada mountains, espcially south of highway 80 where pesticides often contaminate rivers and dams block the essential stream flows.